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BllFs6
April 2nd 04, 04:10 PM
Hi all

I have a few questions about gyrocopters and was wondering if any gyrocopter
"experts" were here to answer my questions...

Or does anyone know of any other internet spots that would be more suited than
this one?

I tried www.rotorcraft.com but it seems to be down..is it just my computer/isp
or is it not working for anyone?

I'll post my question later today if it looks like this is the place to ask
them....

take care


Blll

Dikkie Dik
April 2nd 04, 06:47 PM
BllFs6 wrote:

> Hi all
>
> I have a few questions about gyrocopters and was wondering if any gyrocopter
> "experts" were here to answer my questions...
>
> Or does anyone know of any other internet spots that would be more suited than
> this one?
>
> I tried www.rotorcraft.com but it seems to be down..is it just my computer/isp
> or is it not working for anyone?

I't not working for me either. Have you tried:
http://www.pra.org/ (The Popular Rotorcraft Association)
http://www.gyroplanes.org/ (The British Rotorcraft Association)

Best regards

Gyroplanes
April 3rd 04, 04:25 AM
There are some of us gyroplane folks that haunt this newsgroup. Go ahead with
your questions and I'll do my best to answer them.
Tom

Nishan
April 4th 04, 06:08 AM
Although I am currently pursuing a helicopter rating, I admit that I'm also
interested in gyros. Where to get training in the So. Cal area is what I'd
like to know.

Nishan


"BllFs6" > wrote in message
...
> Hi all
>
> I have a few questions about gyrocopters and was wondering if any
gyrocopter
> "experts" were here to answer my questions...
>
> Or does anyone know of any other internet spots that would be more suited
than
> this one?
>
> I tried www.rotorcraft.com but it seems to be down..is it just my
computer/isp
> or is it not working for anyone?
>
> I'll post my question later today if it looks like this is the place to
ask
> them....
>
> take care
>
>
> Blll

Ken Sandyeggo
April 4th 04, 05:42 PM
http://www.rotaryforum.com/forum/

The old Forum is no longer. This is where all the gyroheads hang out now.

Ken J. - Sandy Eggo






]\"Nishan" > wrote in message .net>...
> Although I am currently pursuing a helicopter rating, I admit that I'm also
> interested in gyros. Where to get training in the So. Cal area is what I'd
> like to know.
>
> Nishan
>
>
> "BllFs6" > wrote in message
> ...
> > Hi all
> >
> > I have a few questions about gyrocopters and was wondering if any
> gyrocopter
> > "experts" were here to answer my questions...
> >
> > Or does anyone know of any other internet spots that would be more suited
> than
> > this one?
> >
> > I tried www.rotorcraft.com but it seems to be down..is it just my
> computer/isp
> > or is it not working for anyone?
> >
> > I'll post my question later today if it looks like this is the place to
> ask
> > them....
> >
> > take care
> >
> >
> > Blll

BllFs6
April 5th 04, 09:39 PM
Thanks for the input guys!

I am posting these questions over at the rotaryforum.com, general discussion
section as well...

Thanks again!

Hi all...

About 2 years ago I developed a real interest in gyro's and basically read
everything over at Mels gyro forum...and I never knew about the now apparently
defunct Norms forum...

So, here comes lots of questions and observations....input on any of these is
highly appreciated.

Okay, one of my main reasons for interest in a gyro is my impression that they
are a lot less sensitive to air turbulence than light or ultralight
airplanes....and I'd hate to have an expensive toy that the weather has to be
nearly perfect to use....I live in Northwest Florida.....any flyers in Alabama,
Georgia, or Florida here who can comment on how often percentage wise the
weather in the southeast is suitable for gyro flying? Note that most of my
flying would be in the few hours after sunrise and the few hours before sunset
and typically 50 miles or more from the coastline....

I recently downloaded Jukka Tervamaki gyro simulator/calculator.....at :

http://www.icon.fi/~jtki/gyrocomp.html


its pretty cool and his website is nice as well....one caution....on some
computers his simulation ONLY appears to work in the metric mode (dont bother
to notify him about it because I already have and he is working on fixing
it)... the really neat thing to do with the program is to change one parameter
at a time in small increments without clearing the screen and you can see whats
important and whats not and when you reach a point of diminishing
returns....for example, input the values for a small, low drag gyro, then start
with a small prop....something like 46 inches, then increase it in say 4 inch
increments up to say 80 inches....and you can easily see where making the prop
bigger doesnt really buy you much more if anything in your top speed......note
that when you first run the program you have to be online for it to download
the data it needs....once that is done, you can get offline and run many
calculations....but once you close out the program you will have get back
online again at first the next time you use it....

Now with his simulation, with as low a drag gyro as is possible....the program
predicts that a 500 lb gyro (26' ft, 8" chord) rotor, with 33 hp at 2083 rpm
using a 64" prop will go at a speed of about 85 miles per hour....does this
sound doable?

The reason I ask is I would really be interested in a small, fast gyro for
short, quick, hops to visit places I often go to on weekends anyway, places
that wouldnt be bad drives except for the fact that I have to usually fight my
way through at least 2 congested towns and there are no direct fast roads from
here to there...and even if the gyro wasn't much faster than driving...an hour
or two of flying would be a lot more enjoyable than the same amount of time in
stop and go traffic ....fortunately there ARE small, conveniently located
airports at where I'd be leaving from and where I'd be going to ...Now if I
could have a small fast gyro that could do 70 that would work, 80 would be
pretty nice, and getting near 90 would be the cats meow...

I understand that due to the rotor aero/dynamics, a shake/vibration is
transmitted down to the control stick (even with perfectly aligned/balanced
rotors)....is this something that is just noticeable...or is it something that
after an hour or two of flying has you just plumb worn out mentally and
physically?


The asymmetry of the forces due to the rotor dynamics...now if you have a 500
lb gyro in level flight.....its obvious that at some point each rotor is
supporting exactly 250 pounds...however at some point in the rotors orientation
the different in lift between the rotors reaches a maximum....roughly what is
the magnitude of this difference? 5 lbs, 20 lbs, 50 lbs.....? In which
direction is this "shake" at its maximum? Side to side, front to back, or
somewhere in between? Is this "shake" mostly caused by the fact the rotors can
only pivot up and down around one point (the teeter? bolt)?...or is it mostly
caused by the dynamics of flexible blades? or is it a comparable mix of both?
Would more flexible blades (though still sufficiently strong) make the shake
better or worse? And for this group of questions let us assume level, steady,
flight and stable rotor rpms....

Rotor blades......what are the lightest ones commercially available and what
are the heaviest? And how much does each weigh? And how much does you typical
single seater 500 lb range gyro's rotor head weigh (not including the mast)?
....trying to get a feel on center on gravity issues here....

For your typical constant chord, no "twist", constant airfoil cross section
gyro rotor blades...what is its lift to drag ratio.....i.e. what would a gyro's
lift to drag ratio be if the mast, passenger section, landing gear exceterra
had ZERO drag...is there a forward speed that it reaches a maximum? At what
forward speed does it start to drop drastically (ie drag is increasing quickly)
?

Now, if you made a rotor system that DID NOT have a constant chord, or constant
airfoil cross sections, or constant angle of attack ("twist") along its
length....roughly how much improvement percentage wise could you hope to gain
over the rotor describe above? Obviously such a rotor would probably only be
"optimum" for one set of conditions....say rate of climb Y at speed X or
maximum lift to drag ratio at cruising speed Z......

Is there a rough way to calculate your vertical descent rate in autogyration
mode? Or does anyone here have the rough numbers.... (this would be handy for
calculating/designing the landing gear system)...

Landing gear.....how much vertical travel does the typical gyro landing gear
system have designed in? Say something appropriate for runways of decently
smooth grass or smoother...

The engine propellor for either tractor or pusher gyros....how close to the
ground can the propellor tips get in normal operations or hard landings before
it feels/seems uncomfortably/unsafely close to the ground?

Well....

Thats probably enough questions for the moment!

take care and thanks again for any input!

Blll

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